itch.io

You tried to simplify it by saying the rules are clear. The rules are anything but clear.

Selling directly is not the same as having itch act as the merchant. One does not "sell" the game to itch so they can sell it to the customer. It is not a transitive chain of equal rules. Itch is an approved seller of adult items. They can collect money for this via paypal.

If you would somehow violate terms of paypal in this scenario, you could not sell it directly either. Obviously.

In the discussion a year ago when many developers where bumped down to direct payment, it was worded with the merchant aspect. Itch does not want to act as merchant in some cases. Note however, that it was not worded that they cannot act as merchant because of any tos violations.

The problem as I see it is the payout from itch to the developer. I wonder how patreon does it. They collect money for the exact same games via paypal, that have been bumped down from collected to direct.

If you comply with paypal's content rules

But ... what are the rules for business to business transactions? The tos you can look at are business to consumer rules and there you absolutely can sell adult content (conditions apply). So what information does this give us, if you blanket say, just comply to the rules and everything will be fine? To me it gives zero information.